Stabilized cyclized rubber



Patented Aug. 7; 1945 .1 T is in en o e ates;.to e abilization of ac lizedy u e sam more parti ula y t v th o aldeh de-cond ns onprod cts off p lyel t n lpp am ne -to in i he-Phot chem- ,ica rioration thereof. v I p 'lfher e are yarious. types ,f cyclizedlrubbers whi h; has? b s Qi l ll i other ttr sa a a-been QGSQ-IiW JI -ih i a e Thi invention, relates particularly to the, st b lization f tn. t zi' li fid abit t d ivat v r o u d w trs atm 9 with I t an ieoia amphoterm; metal, or. a ,7 such aschlgrostannic acid; whichare of the type known to the trade as Pliolite andproduced by The Good- ...rea: shutt r mm-We v e intention,- yt ev i a p abl t the other iles su h a help ouc s, P uce :by henel l onm dor e i n a d 1 b d ogen .fl de 4 The i inhibitors .useful in the invention are preiier ead n an d y e t a e ye k l n fpolyaininelwith.attendantelimination of water to produce aoondensation product.

.tbe we n aldehydes and i i'al ei polyainine's areyery complex as demonstrated-by the following equationsand formulas infwhich acetaldehyde and diethylehe triamine are used \iforillustrative 'purposes For-example, ifthe terminal igroups 0f the a'mine' are primary amino, one or both of them may react' toiomn' an al-' k-ylidene ty'pew'oompound as -followingequation z --(-1 f "c mono NH+0,Hl'NH=c,H4 NH,

the terminal groupsare either primary or seconaary amino, two molecules "of 'theamine may;

- '-l5e" linkd-- throu'g"h the residue of the carbonyl compound, as showni nEquation 2:" i

2 omono 2NH'kCHNH-OzH4NHa rCIHl-Q QAIILfNH- NJfiQCBHlrNHwCzHfiNH: 7k. 121150 CH1" ddition, when the intermediate aminov group tiyejhydrog'en, 1.3a, iaresecondary have/cnossmka e ,b twe 1'; several molecules of amine'through the res v conceivable that iother: StypeS :of re- H'i V. m "3 Claims represented by the duejof the .eaiboriyi'cornpoundas illustrated'by q Y v f I t I lsmmzeseyc g a ss f I Harold J. (isterlroif uyahoea -.Fal sOh i.o,' a sl'gnor to Wing'foot' Corporation, Akron, Ohio, at

porporation of Delaware um i Application March 12, 1942,

serial No. 434,363

(CLMilli -F7134);v that vario combinations and continuations' of go ng type reactions. may take place, it is that the reaction products may contain einumbe'r 'offindividual compounds.

7 Thepreparation of the photochemical inhibioisoffthe invention is illustrated by the follow- U 'Edr'ample 1 v The maximum amount of aldeh de which theoretically canv be reacted with diethylene triamine is 2 mols of thealdehyde to each mol of the amine. This example represents reaction of :diethyle'ne triamine; zwith. itformaldehyde in this proportion.-c':* T0138) grams. of diet-hylene triamine, mg-rams (4i-% .\xcess) of137%:formaldehydewere 5 added'islowly; with stirring, the mixture becoming ",qiiitea'liscous toward the end of the addition. One hundred c. ztof :."benze,ne were then added an themixtmze was refluxed, watervbeing removed by means ioi a trap in 213116 reflux'line. When the evolution ofrwater, ceased and, all of the water had @been trapped out; the benzene was distilled pfhat reducedpnessure. produ t wasa v s- 40,0115, ,oranee'l qu d and W sobtain d i th e cal yield. v

mmzz e 2 grams'ffof trithylehe tetramine, keeping t e-temperatiire so-co c. After all the aldehyde'had Joeen addedfthe temperature was raised "to 110-120? C; nd'thewater Was distilled out undenreddcgd pressure-"'Ifhe'product was an aldehyde in the proportion of one mol of amine to two mols of aldehydeas follows: To a solution' of 27.5.grams of triethylene tetramine in e no 0. vcrof tbenzene, :31 grams of 37%: formalde- "hydewere addedaslowly iwith stirring. :The mixturelwasrefluxedcforsix hoursg the Water formed lbeihgiltrappedgout. "Benzene was thereafter-removed iby disti'llation at reduced pressure leaving m-a rgel'residue, Whichvupon heating to 200 C. beioame aul-iquici remainedas such after cooling. I The 'yi'eld'was quantitative.

I Tmethyleneltetra-mine can theoretically be re- 55 acted with an aldehyde in the proportioniof one product was a viscous, dark-red semi-solid. The

yield was quantitative for the reaction product of one mol of triethylene'tetramine and three v mols of formaldehyde.

Example 5.

Tetraethylene pentamine was reacted with formaldehyde in equimolecular proportions as follows: Thirty-two and two-tenths grams of 37% :formaldehyde were added slowly to 75.2 grams of tetraethylene pentamine, maintaining the temperature at GO-70 C. The temperature was then raised to 110-115 C. and maintained for one hour. The mixture was then heated first to 250 C. and then to 200 C. at -40mm. pressure until all of the water present was removed. The product was a dark-orange, viscous liquid and was obtained in 95% yield.

Example 6 Tetraethylene pentamine .was. reacted with formaldehyde in the ratioof one molofamlne to two mols of aldehydeas follows: .Sixty-one grams of 37% formaldehyde .wereadded to. .71 grams of tetraethylene pentamine, keeping the temperature at 6'0-70 .C. The temperature was .raised-t0 105-110 C. for l fl hours, and-themixture was then'heated to270 C. at atmospheric 7 pressure followed by heating at the same temperature at a slightly reduced pressure until no more water distilled off. The product was a darkred, slightly fluorescent liquid and wasobtained in 91% yield. 1 l

' Example 7 Tetraethylene pentamine was reacted with formaldehyde in the ratiofo'f'two mols of amine to five mols of aldehyde as follows: "Seventy-four grams of 37% formaldehyde were added slowly to sixty-nine grams of tetraethylene' pentamine, keeping thetemperatureat 60-70? C. The mixture became somewhat gelatinous toward the end of the a'ddition'o'f the aldehyde. The reaction mixture was then heated at 105-110 C. for 2 hours and was dried by heating to 230 C. at 40-60 mm. pressure. The product was a darkred, slightly fluorescent, very viscous liquid and was obtained in almost theoretical yield.

Example 8 i Tetraethylene pentamine .reacted with formaldehydeintheratio of one. mol ofamine to three mols of aldehyde .as .foIlows: ..Eighty-six and four-tenths grams .of ..37%.. fonnaldehyde were .added, in small .portionsto 167.1, grams of .tetraethylene ,pentamine .and .the .mixture .was

thenheated at ,105- 110..C. fortwo hours. The water present .was .then removed by .heating :to 200 C. at -80 mm. pressure. The product was a dark-red, slightly fluorescent, viscous liquid and, was obtained in practically ..quantitative pentamine.

heated at 105-110" C. for three hours and was Example 9 Tetraethylene pentamine theoretically can be completely reacted with an aldehyde in the proportion of one mol of amine to three and onehalf mols of aldehyde. This example demonstrates the reaction of tetraethylene pentamine with formaldehyde in this .ratio. ..Ninety-eight and two-tenths grams of 37%*"'formaldehyde were added slowly to 65.5 grams of tetraethylene The reaction mixture was then dried by heating to 200 C. at 50-70 mm. pressure. The productwas a dark-red, very viscous liquid and obtained in 92% yield.

' "Example 10 Ammonia, tetraethylene pentamine and formaldehyde were reacted in the proportion of one mol of ammonia to one mol of the amine and two mols of the aldehyde as follows: Seventy grams of tertaethylenepentamine were mixed with nineteen grams of 33% ammonium hydroxide and 00 c.c.of water. Sixtygrams of 37% formaldehyde were then added slowly; maintaining the temperature at 50-60"--'C: Th'e-mixture'was refluxed'for-two hours,- after which125 c.c. of benzene were-addedandthe refluxing was continued. The wateripresent and formed by the reaction was trappedfout, and. when the product was dry; the benzene'was removed "by-vacuum distillation; The product 'was'a red, viscous liquid and {weighed eighty-nih gramS.

, I reahipze 1'1 Diethylenetriamine was reacted with butyraldehyde in the ratio ofone mol'of amine to two mols -of-aldehyde according to the general procedure employed in the foregoing examples. After-all of the aldehydehadbeen added, the mixture was heated "on-a steam bath for eight hours, and the "water was then removed by heating to a still higher temperature. The product wasa dark-yellow oil'and was obtained in 98% 'yield.

d Em- 1111612" Tetraethylene,Lp ntamine .was reacted with butyraldehyde; in.;the ratio .of; one ;mol of amine to .threeandpne-half ,mols-;of, aldehyde as followsz Twenty-six .partss of. ::butyraldehyde were added in small portions to 18.9.parts oftetraethylene pentamine. Themlxture was heated on a steam bath forone hourand was then refluxed for ,one hour. The. water was removedby heating at atmospheric pressure. The product i was a; straw-co lored ;liguid,. thirty parts b weight being obtained. E m elf.

Tetraethylene pentamine was reacted with hexaldehyde in the ratio of one mol-of amine to two and one-half mols of aldehyde as follows: Fifty-five and two-tenths grams of hexaldehyde were added slowly to34z8 grams of tetraethylene pentamine. 'After the initial exothermic reaction had subsidedythe mixture. was heated to 80-90" C. andwasjthen allowed to stand at roomtem- 'pe'rature for seyeral'hours. f Sev'en' grams of hexaldehyde were then added, and the mixture was heated to 150 C. until all the water had been removed. The product was a reddish liquid.

j m zje 14 Tetraethylene pentamine was reacted with .heptaldehyde. .in .theuratio of one mol of amine .to; two mols ..of aldehyde by :heating at -100 C.

for'eight hours; The waterwas then distilled. off at atmospheric pressure. The .productwas a yellow liquid and was obtained in 90% yield.

. Example Tetraethylene pentamine andv alpha-ethylbeta-propyl acrolein were reacted in the ratio of one mol of amine to two molsof the aldehyde as follows: To.3'l.8 grams of tetraethylene pentamine were I added 50.4 grams of alpha-ethyl-betav'propyl-acrolein''containingone gram of butyric :acid. iThe mixture was heated to'120130 C. for five hours, and theqtemperaturewas then raised to 200 C. until all'the water had been removed.

' The productwas a dark, reddish oil andwas obtained'in practically quantitative yield.

Eaample 16 7 Thirty-one grams of the condensation product of equimolecular proportionsof diethylene triamine and crotonaldehyde were reacted with 77.5

grams ofZ-ethyl-hexyl-bromide, using 16 grams of sodiumhydroxide dissolved in 'c. c. of water to absorb the hydrogen bromide formed, as follows: The aldehyde-amine was heated to 140 C.

and aboutone half of .the2 ethyl-hexyl bromide wasadded at such a rate that the temperature did not exceed 170". C; The temperature ,was then maintained at 140-150 C. for thirty minutes, one- .third of the sodium hydroxide was; added and the mixture was refluxed for ten minutes. The re- Example 17- Diethylenetri amine and hexaldehydewere reacted in the proportion of one mol of amine to 7 two mole of aldehyde as follows: One hundred grams or hexaldehyde wereadded to 51.5, grams of'dithylene trial-nine. After the exothermic reaction had subsided, the mixture was heated to a temperature, sufllci' for a'periodof one hour. The water was then removed by, heating at 125? C. under reduced pressure. Fifty-nine grams of this condensation product were then reacted with 36 /2 gramsof. hexyl bromide, using 8 ;9grams of sodium hydroxide dissolved 11120 :c.' 'c. of water to absorb the hydrogen bromide formed, as follows: The aldehyde-amine was heated to 140 C. and aboutone-half of the hexyl bromide was then added slowly with agitation. The reaction mixture became turbid and separated into, twolayers. After heating at 110 C. for about'onehalf hour, approximately one-fifth of the sodium hydroxide solution was added, and the mixture was heated for five min- I I remainder 0f- ,the bromid was then added, and, after refiuxing'for thirty minutes, the remainder of the sodium hydroxide solution was utes. The

' added! The heating was -'then continued for another-thirty minutes} The water was removed byheating to 20090} at mm. pressure. On 1 standing for a few hours, the dried product separated' into two layers. Thelo'wer layer was tested as photochemical inhibitor." 1 v I 7 Example 18 :JN, N '-dihexyl tetraethylene pentamine was reacted with butyraldehyde in. equimolecular projthen dried by heating,

ent to cause gentle refluxing" portions as follows: Six and eightetenths grams hexaldehyde were added to fifty-two grains of N,

N""-dibenzyl tetraethylene pentamine, and the of butyraldehydev were added to forty-two grams of I l,, I If""-dihexyl tetraethylene pentamine, and the mixture was heated on a water bath for three and one-half hours. The product w'asjan orange oil.. M

. v r Example 19 Eduimolarproportions of hexaldehyde andN,

N"-dibenzyltetraethylene pentamine were reacted as follows: Eleven and one-tenth gramsof mixture washeated to 200 C. The product was dark-red, fifty-seven grams being obtained.

Example 20" N, N, N"-tri(o-methyl cyclohexyl) diethylene triamine was prepared by the action of ethylene dibromide on o-methyl cyclohexylamine. The 'productwas separated from N, N dim-methyl cyclohexyl) ,ethylene diamine and N, N'.-dicycl0- hexyl piperazine-by distillation in vacuo. Thirtyeight grams of this product were mixedwith three grams of, para formaldehyde and one-hundred grams of benzene, andthe mixture was refluxed, the Water being separated out by means of atrap. At the end of one and one-half hours, no more ,water'was given off. The benzene was evaporated off until the weight of the solution was 131 grams.

This product was a 30% solution of the reaction product, which 'was suitable for use without further purification; This product may also be made in the-absence of benzene, in which case it is obtained as a soft,tacky resin.

Example 21 Seventeen and one-tenth grams of butyr aldehydejwere added to 41 grams of N-(beta-morpholylethyl) ethylene diamine, and the mixture was heated for three hours on a water bath; 'The reaction product was then completely driedby heating under reduced pressure. The product was a straw-coloredliquid and weighed 54 grams.

ramble 22 Forty-five. (grams of di( beta-morpho1y1ethyl) amine were reacted with. 6.6 grams of butyraldeliquid;

hyde by heating-ona water .bath for three hours.

The mixture was then dried by heating underreduc'ed pressure. The product was a reddish Example 23 Fifty-three and two-tenths grams of N -(betamorpholylethyl) triethylene tetramine [obtained 1 by reacting equirnole cular proportions of tetraethylenepentamine and fi,fl-di(ch1orethyl) ether] were reacted with 20.5 grams of hexaldehyde by heating on a steam bath'for three hours. The water was removed by heating under reduced pressure. The product was a viscous, dark orange-red liquid weighing 70 grams.

Example 24 Fifty-eight grams of N-(beta-morpholylethyl) triethylene tetrarnine [obtained by reacting equimolecular proportions of tetraethylene pentamine and.,s,;8- di(chlorethyl) ether] were mixed with 16.1 grams;of"bu tyraldehyde and heated on a steam bathvf'or fourand one-half hours. The water was removed underreduced pressure. The

productvv as a reddish, oily liquid and was ob? tained in theoretical yield.

. Example Fifty grams of N,N"-di(beta morpholylethyl) diethylene triamine [obtained by reactingone' molar proportion of tetraethylene pent-amine with two molar proportions "of p,,B'-di-chlorethyl) ether] were treated with 15.2 grams of hexaldehyde by heating the reaction mixture on a steam bath for five hours. After drying,.,the product weighed 58.3 grams, which, was. equivalent to a 93% yield. 1 111 T Example 26 Fifty grams of N,N di(beta-morpholylethyl) diethylene triamine were reacted with 10.9 grams of butyraldehyde in a manner similar to that employed in the preceding example. The product was obtained in theoretical yield.

Example 27 Fifty-eight and two-tenths grams of triethyl- Fifty-six' and seven-tenths grams of tetraethylene pentamine were reacted with nine grams of formaldehyde. A substantially theoretical yield of the condensation product was obtained. The components were reacted in equimolecular proportions.

As demonstrated in the foregoin examples, various aldehyde and polyalkylene; polyamines may be employed in preparing th desired stabilizers. Other aldehyes and polyalkylene, poly amines may be substituted for the specific materials used in the various examples. Thus the aldehyde may be aliphatic, cycloaliphatic or alicyclic, or it may contain a ring-substituted aliphatic radical, such as aralkyl, furfuryl and similar radicals. Also included are aromatic compounds although these are not preferred. The aldehydes preferably should not contain acidic substituents, such as carboxyl or sulfonic radi cals, or other substituents whichwill react with the polyalkylene polyamine, but they may contain various neutral or basic substituents, such as alkyl, aryl, aralkyl, alkoxy, aryloxy, amino, ester, amine salt, ether, etc., groups,'which are substantially inert in the reaction with th e. polyalkylene polyamine and do'not destroy the, inhibiting. effect of the final products. Representative examples of aldehydes are acetaldehyde', propionaldehyde, acrolein, aldol, benzaldehyde, vanillin, piperonal, cyclohexanal, beta-chloro .butyraldehyde, furfural, phenylacetaldehyde, and

the like. The polyalkylene polyamines which may be used comprise compounds having the structural formula;

hydrogen, and .x is a whole number, the polyala. kylene 'polyamine containing at least one amino hydrogen so that condensation with the carbonyl compound: may beeffecteda a 'lnclu'dedi are com pounds havingthestructural formula 1 RNHR[ l ]NHR in, which R is selected from the group consisting of aliphatic, cycloaliphatic, alicyclic, and ringsubstituted aliphatic, R is alkylene, R." is selected from the group consisting of aliphatic, cycloaliphatic, alicyclic, and ring-substituted aliphatic' radicals and hydrogen, and :r is a whole number.' The simple unsubstituted polyalkylene polyamines having theystructural formula um-R'iNH Roz-isl s r in which R is alkylene and :c is a whole number are readily available and generally yield particularly good inhibitors and constitute a preferred' class of materials. Also included are morpholyl and analogous compounds having the structural formula I in which R isalkylene, R is oxygen or sulfur, andim is a whole number. -Also included are in which R is selected from the group consisting of aliphatic, cycloaliphatic, alicyclic, and ringsubstituted aliphatic radicals and hydrogen, R is' alkylene and x is'a whole number. In each of the foregoing definitions'and elsewhere' in the specification and claims, the'term aliphatic includes saturated and unsaturated, straight and branched chain radicals, and the term ringsubstituted aliphatic includes radicals such as aralkyl, furfuryl, tetrahydrofurfuryl and the like. Also, in each of the foregoing formulas, a: is preferably a number from one to ten, inclusive. The alkylene radicals represented. by R include cycloaliphatic radicals, ]such as the cyclohexylene radical (-CsI-I4). The aliphatic, cycloaliphatic, alicyclic, ring-substituted aliphatic, and alkylene groups are preferably hydrocarbon, but they maycontain various substantially neutral or basic substituen ts such as alkyl, aryl, aralkyl, alkoxy, aryloxy, ester, amine salt, ether, etc., groups, whichf'are.substantially inert in the reaction with the aldehydejand do not adversely affect the inhibiting properties of the product. .In addition,.and particularly 'in the longer chain, higher "molecular weight polyamines, itis possible to replace some the aliphatic, cycloaliphatic, alicyclic, ring-substituted aliphatic, and alkylehe radicals with aromatic radicals andto have some acidicsubstituent s such ascarboxyhhydroxyl, etc. radicalsupresent. These modifications tend to-lessen the inhibiting effect of the products and; they. are genera'lly not desirable. However, when they are judiciously used, the products willstill retain some inhibiting power. Such modificationsareequivalentsof the compounds of the inventionaand are intended to becoveredbythe claims.

The aldehyde compound and polyalkylene polyamine may be reacted in a wide range of pro portions. The minimum amount of aldehyde which can react with the amine is'one-halffmol to 9 mols of :amine.:-' Al'so'as h'as been previously 'cule or a given polyalkylene polyamine. .maximum may be generally stated as one molof indicated in'the description of the invention there are. certain theoretical maximum proportions in which the aldehyde will react with a single mole- This aldehyde to every two amino hydrogen atoms. It must also be remembered that some aldehydes tend to polymerize and, therefore, in at least some instances more than the theoretical amount may be employed. The proportions of reactants are not critical since the reaction products of aldehydes and polyalkylene 'polyamines are more or less efiective inhibitors regardless of the amount of combinedaldehyde. Also if amounts of aldehyde greater or less than the reactive limits are employed, the result'is merely that the crude product contains some unreacted starting material. 1 1 d Small amounts of acidic or alkaline condensation catalysts may be present in the reaction mixture, but the reaction "proceeds well without such added'materials, and, therefore, the latter condition is preferred in the practice of the invention.

It is also to be understood that mixtures of polyalkylene polyamines may be employed. Also simple. amines, such as methylamine, benzylamine, furfurylamine, etc. may be employed in conjunction with a polyalkylene polyamine to produce modified compounds coming within the daylight that the same paint containing no stabliizer showed in 39 days. For this purpose but one-half a per cent of the condensation product was used based on the weight of the cyclized rubber. Additions of about 2% bloomed out on the surface of the paint. The product of Ex- 1 ample 2 likewise gave good stabilization when added in amounts of about one or 2% to paint. The other condensation products of this invention also stabilize cyclized rubber contained in paint compositions.

A moistureproofing composition was prepared from a partially oxidized cyclized rubber with a softening point of about 55 C. which contained a considerable percentage of parafiin. Thi was coated onto glassine paper which was hung in the window in direct sunlight. The heat-sealing properties of the sheet were materially improved by the stabilizer of Example 5. Samples of the sheet coated with moistureproofing formulas which were identical except that one contained the stabilizer and one did not were hung in the window and'tested from time to time. The coatinvention, which are effective photo-chemical in hibitors. Example 10 illustrates-the use of amamine according to this variation of the invention. Any temperature at which condensation between the aldehyde and amine takes place may be used. The reactions ordinarily proceed at room temperature with the evolution of heat, but temperatures above and below room temperature may be employed. Inasmuch'as thereaction is generally stronglyexothermic, some care should be exercised to keep it under control. Obviously the reaction should be conducted below decomposition temperatures. These vary somewhat depending upon individual compounds and the time of heating but are usually about 250 to 300 0. Also in accordance with general rules it will sometimes be desirable to start the reaction at a low temperature and progressively increase the temperature as the reaction proceeds toward completion.

1 The inhibitors are customarily used in small amounts, for example, not more than several per cent by weight based on the weight of the cyclized rubber.

The tests-conducted show that the compounds of this invention prolong the life of paints produced from cyclized rubber and also prolong the lift of moistureproofing compositions produced by cyclized rubber. For instance, the products of Examples 5, 27 and 28 added to a paint of a cyclized rubber showed the same degree of deterioration after 205 days of exposure to diffusedmonia in conjunction with tetraethylene penting containing the stabilizer retained its good heat-sealing properties after nine days exposure whereas the control sheet retained comparable heat-sealing qualities for only five days.

Similar tests were, run on moistureproofed sheets to which the stabilizers of Examples 5 and 2 were added. These prolonged the life of the cyclized rubber 1'70 and 140% respectively. The other condensation products referred to herein likewise stabilize cyclized rubbers used in moisturep-roofing compositions.

The paints and moistureproofing compositions may contain fillers, coloring materials, plasticizers, etc.

What I claim is:

1. A cyclized rubber having admixed therewith in a quantity sufficient to act as a stabilizer the condensation-product of an aldehyde and a polyalkylene polyamine having the structural formula in which R is alkylene, R is selected from the group consisting of aliphatic, cycloaliphatic, alicyclic, and ring-substituted aliphatic radicals and hydrogen, and x is a whole number from 1 to 10, said polyalkylene polyamine containing at least one amino hydrogen atom.

2.. A cyclized rubber having admixed therewithin a quantity sufficient to act as a stabilizer a condensation product of formaldehyde and tetraethylene pentamine.

v3. A cyclized rubber having admixed therewith in a quantitysufiicient to act as a stabilizer a condensation product of formaldehyde and triethylene tetramine.

HAROLD J. OSTERI-IOF. 

